Multi-adaptability supercapacitor electrolyte based on Na-MMT/PDADMAC and application in wide temperature range

Abstract

Polyelectrolyte is widely used in supercapacitors, but its poor matching with electrodes and narrow operating temperature range limit its further application. Here, Na-Montmorillonite/Poly dimethyl diallyl ammonium chloride (Na-MMT/PDADMAC) composite polyelectrolyte was prepared by solution intercalation and assembled into solid supercapacitor with three different electrodes (carbon, NiCo(OH)2 and Polypyrrole electrode). The result shows that Na-MMT/PDADMAC polyelectrolyte has a good matching performance with the three kinds of electrode. After 1000 cycles at 15℃, 35℃ and 50℃, the capacitance of all electrodes basically remain above 90%, showing wide operating temperature range. More interestingly, with the increase of Na-MMT, the combustion resistance of Na-MMT/PDADMAC solid polyelectrolyte film gradually increases, and the maximum flame resistance time can reach 50 s, indicating that the solid electrolyte film has good heat resistance. The good matching and wide temperature adaptation range with electrodes are mainly attributed to the addition of Na-MMT, which not only increases the ion migration rate, but also limits the thermal decomposition of PDADMAC molecular chain.